Links between Exercise Capacity, Exercise Training, and Metabolism.

Exercise capacity of an individual describes the ability to perform physical activity. This exercise capacity is influenced by intrinsic factors such as genetic constitution and extrinsic factors such as exercise training. On the metabolic level exercise and metabolism are linked.

Targeting Mitochondrial Metabolism to Save the Failing Heart.

Despite considerable progress in treating cardiac disorders, the prevalence of heart failure (HF) keeps growing, making it a global medical and economic burden. HF is characterized by profound metabolic remodeling, which mostly occurs in the mitochondria. Although it is well established that the failing heart is energy-deficient, the role of mitochondria in the pathophysiology of HF extends beyond the energetic aspects.

Knockout of the Complex III subunit Uqcrh causes bioenergetic impairment and cardiac contractile dysfunction.

Ubiquinol cytochrome c reductase hinge protein (UQCRH) is required for the electron transfer between cytochrome c and c of the mitochondrial cytochrome bc Complex (CIII). A two-exon deletion in the human UQCRH gene has recently been identified as the cause for a rare familial mitochondrial disorder. Deletion of the corresponding gene in the mouse (Uqcrh-KO) resulted in striking biochemical and clinical similarities including impairment of CIII, failure to thrive, elevated blood glucose levels, and early death.

The IGF-1R Inhibitor NVP-AEW541 Causes Insulin-Independent and Reversible Cardiac Contractile Dysfunction.

The antitumor treatment NVP-AEW541 blocks IGF-1R. IGF-1R signaling is crucial for cardiac function, but the cardiac effects of NVP-AEW541 are ill defined. We assessed NVP-AEW541's effects on cardiac function and insulin response in vivo and in isolated working hearts.

Targeting the alternative oxidase (AOX) for human health and food security, a pharmaceutical and agrochemical target or a rescue mechanism?

Some of the most threatening human diseases are due to a blockage of the mitochondrial electron transport chain (ETC). In a variety of plants, fungi, and prokaryotes, there is a naturally evolved mechanism for such threats to viability, namely a bypassing of the blocked portion of the ETC by alternative enzymes of the respiratory chain. One such enzyme is the alternative oxidase (AOX).

Genetically determined exercise capacity affects systemic glucose response to insulin in rats.

Aerobic exercise capacity is inversely related to morbidity and mortality as well as to insulin resistance. However, exercising in patients has led to conflicting results, presumably because aerobic exercise capacity consists of intrinsic (genetically determined) and extrinsic (environmentally determined) parts. The contribution of both parts to insulin sensitivity is also not clear.

High-fat diet affects skeletal muscle mitochondria comparable to pressure overload-induced heart failure.

In heart failure, high-fat diet (HFD) may exert beneficial effects on cardiac mitochondria and contractility. Skeletal muscle mitochondrial dysfunction in heart failure is associated with myopathy. However, it is not clear if HFD affects skeletal muscle mitochondria in heart failure as well.

GLP-1 Improves Diastolic Function and Survival in Heart Failure with Preserved Ejection Fraction.

Heart failure with preserved ejection fraction (HFpEF) has emerged as a public health burden with currently no effective medication. We assessed the treatment effects of the incretin hormone glucagon-like peptide-1 (GLP-1) on cardiac metabolism and function in a model of HFpEF. Following aortic banding, rats developed HFpEF characterized by diastolic dysfunction, pulmonary congestion, and poor survival (38%).